The Clinical Core of this project will function to carefully characterize a cohort of subjects with scleroderma, drawn from two large referral centers, followed prospectively to link their clinical data, disease progression and severity with biologic mechanistic data. The specific aims of this proposal are: Aim 1: To develop and maintain a clinical data repository of key clinical disease parameters in a prospectively followed cohort of subjects with scleroderma and match these clinical data with subject tissue and blood samples, which will be stored and maintained by the Clinical Core. The clinical core will also coordinate the collection of blood samples for preparation of RNA from peripheral blood mononuclear cells (PBMC) to be carried out by the microarray core. It will also coordinate the collection of skin biopsies for fixation and histological evaluation and for RNA preparation in coordination with the microarray core. Aim 2: To provide investigators in Projects 1, 2 and 3 with clinical data and statistical resources to perform analyses correlating gene array and biomarker data with matched clinical data collected longitudinally.